FINK—THE LICHENS OF MINNESOTA. 105 
Family BAEOMYCETACEAE. 
One of the two genera of this small group seems to stand out distinctly enough to 
warrant the recognition of the group as a family. This is the genus Baeomyces, 
Here we have a well developed stipe in company with apothecial characters related 
to those of the Lecideaceae rather than of the Caliciaceae, where the stipe is also 
found. It is apparent enough that the Baeomyces may have been evolved from the 
Lecideas by the development of a stipe. And, indeed, the relationship as to thallus, 
apothecia, and spores seems very close. But when we turn to the other genus, 
Icmadophila, we are confronted with difficulties which make it questionable whether 
that genus should be placed in the present family or with the Lecanoraceae. The 
relationships of the genus are discussed in connection with the description of it, and 
here it need only be said that the spore characters are such as might indicate a close 
relationship with Biatorina or Bilimbia, and that this fact adds weight to the present 
disposition of the genus. 
The family is represented in the State by but two genera and as many species. 
Both species are found in the northern portion of the State. 
BAEOMYCES Ebrh. Beitr. Naturk. 4: 149. 1789. 
The thallus is commonly crustose, though in one North American and a few foreign 
species it reaches a subfoliose condition. In all of the crustose species, at least, the 
cortical layers are absent, though algal and medullary layers may usually be distin- 
guished, the former usually covered above by a thin layer of gelatinized hyphe. 
The hyphal rhizoids are few. The alge are probably a modified form of Cystococ- 
cus, but Gloeocapsa-like colonies are also frequently found in some of the species. 
The apothecia are borne upon stipes, which are devoid of algal cells and thus more 
rudimentary structures than the podetia of the Cladonias. The stipes, accordingly, 
are composed entirely of hyphx, those forming the outside being closely packed and 
running longitudinally, while those toward the central portions are more loosely 
and irregularly arranged. , 
The apothecia are single or more or less grouped upon the stipes. They are sur- 
rounded by a proper exciple, which may disappear when the disk becomes very con- 
vex. The hypothecium is commonly pale and the hymenium pale or brownish 
below and darker above. The spores are simple and colorless in the genus as here 
limited. . 
The members of the genus are clearly related to the Cladonias and the Lecideas, 
and scarcely more closely or certainly with Icmadophila, which genus is included 
_with Baeomyces by Tuckerman. 
A single species is found in the State. On rocks and earth. 
Type species Lichen baeomyces L. f. Suppl. Pl. 450.1781. (Baeomyces roseus Pers. 
Ann. Bot. Usteri 7: 19. 1794.) 
Baeomyces byssoides (L.) Ach. Lich. Suec. 82. 235. 1798. Puate 10, A. 
Iichen byssoides L. Mant. Pl. 1: 133. 1767. 
Primary thallus crustose and rather thin, granulose, the rounded granules becom- 
ing leprose-squamose and crenate-lobulate, commonly widely and irregularly spread 
over the substratum as a continuous or more or less broken crust, sea-green or more 
commonly varying toward greenish or whitish; stipes unbranched (or rarely divided 
above) and scarcely ever more than 3 or 4 mm. long, usually shorter and sometimes 
scarcely developed; apothecia commonly convex-pileate, small to middle-sized, 
0.7 to 1.75 mm. in diameter, the disk from brownish flesh-colored to dark brown, the 
exciple evanescent; hypothecium commonly pale; hymenium pale brownish below 
and darker above; paraphyses simple or frequently branched, commonly enlarged 
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